28-04-2011, 02:48 PM
Presented By
Sourabh D. Patil.
Ganga H. Tepugade.
[attachment=13019]
Introduction
General practice is to use shallow foundations for the foundation of structures if the soil close to the ground surface possesses sufficient bearing capacity. However, where the top soil is either loose or soft, the load from the superstructure has to be transferred to deeper firm strata. In such cases, pile or pier foundations are obvious choice.
There is also a third method which may in some cases prove more economical than deep foundation or where the alternate method may become inevitable due to certain site and other environmental condition. This third method comes under the heading soil improvement. Soil improvement is frequently termed soil stabilization, which in its broadest sense is alteration of any property of a soil to improve its engineering performance.
Basic Concept
The behavior of a structure depends upon the properties of the soil materials on which the structure rests.
Soil improvement :
Increases shear strength.
Reduces permeability.
Reduces compressibility.`
METHODS OF SOIL IMPROVEMENT
• Mechanical compaction
• Dynamic compaction
• Vibroflotation
• Preloading
• Sand & stone columns
• Use of admixtures
• Injection of suitable grouts
• Use of geotextile
Methods Of compaction
Rolling
Ramming
Tamping
Benefits
It is method which is used to improve soil conditions on large scale; like road construction.
When available funds are less & labour available are more then compaction by mechanical means is obvious choice
GEOTEXTILE
INTRODUCTION
Infrastructure is the basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function.
The textile material has the basic property to develop shear-stress when subjected to load.
Concrete commonly used in civil to engineering application, to develop and absorb compression stresses and shear stresses.
In conventional concrete structure the civil engineers use steel for reinforcement or for absorbing shear stresses.
Now this job can be best done by geo-textile because of their fundamental property of developing shear-stress when subjected to load.